The little match girl a character in Hans Christian Andersen's fairy tale, curiously stares at the bubbles popping up from the match head. In the Communication on
page 9580 ff., Z. R. Shen, J. C. Yu et al. unveil the mystery of the magical scene: phosphorus (match head) in water can generate hydrogen (bubbles) under
illumination. The image (designed by Z. F. Hu) depicts the process of hydrogen evolution on fibrous-phase phosphorus, a record-breaking photocatalyst.